The progress of human depends upon the exploitation of different natural resources. The utilization of soil, water, coal, electricity, oil, gas and nuclear energy is very important for the development of nation. Any matter which is required or used to sustain life or livehood is termed as a resource.The basic ecological variables - energy, space, 'time and diversity are sometimes combined are called natural resources.In other world resources are all these requirements of organisms, population and communities which trend to help in accumulation of energy by their increased availability.Natural resource is defined as form of energy and or matter which is essential for the functioning of organisms, population and ecosystems. Natural resource refers to any form of energy or matter essential for the fulfillment of physiological, socio­economic and culture needs both as undivided or a community.This natural resource is maintaining ecological balance among them. The natuial resources include all the land, water, minerals, vegetation, wildlife and sceneries all of which remain useful to human society in one way or other. Natuial resources are classified into following three categories:(1) Renewable resources:Resources that can be replenished through natural cycles are known as renewable resources.These resources are able to increase their abundance through reproduction and utilization of simple substances e.g. Fish, forests, crops, woods, leather, water and soil solar energy, wood and wood products.(2) Non Renewable Resources:Resources that cannot be replenished through natural process are known as non renewable resource.There amount is limited and cannot increased, e.g. Metals (iron, copper, zinc), fossil fuel (coal and oil deposits) minerals and salts (phosphates, nitrates, carbonates) and stone once a non renewable resource is consumed it is gone forever. Non-renewable resources can further be divided into two categories (a) Recyclable and (b) Non-recyclable.
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Soil, wood, oil. minerals, petroleum, water are considered natural resources because they occur in their natural form and are not made by human beings.

Humans can only modify natural resources. The energy that makes natural resources comes from geochemical, geophysical and solar energy.

The exploitation of nature and natural resources can be dated back to the advent of humankind and the very start of civilization. Earlier people used to cut trees for fuel, for building materials for boats and for shelter. There are two kinds of natural resources- renewable and nonrenewable.

Wood which is one of the main natural resources has the advantage of being renewable. Fish, animals and forests can renew themselves if they are not over-harvested. Forests can be replanted and, in time, the wood that was used can be replaced.

However in recent times, we have been witnessing the cutting down of trees at alarming rates. In cities it is becoming, increasing difficult to

see a green patch. If we do not replace these trees at the same speed as we are using them then very soon this resource will be expended. The cutting of trees also results in loss of ecosystems and soil erosion, and less rainfall. When fossil fuels were discovered they momentarily took the pressure off wood.
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